What is the value of pi (π) to 2 decimal places?
- A. 3.12
- B. 3.14
- C. 3.16
- D. 3.18
Correct Answer: B
Rationale: The value of pi (π) up to two decimal places is 3.14. Pi is a mathematical constant representing the ratio of a circle's circumference to its diameter and is commonly approximated as 3.14. Choices A, C, and D are incorrect as they do not match the standard approximation of pi up to two decimal places.
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Convert 5 3/4 to a decimal. Round it to the nearest tenth.
- A. 5.75
- B. 5.7
- C. 6
- D. 5.8
Correct Answer: D
Rationale: To convert 5 3/4 to a decimal, divide the numerator (3) by the denominator (4) to get 0.75. Adding this to the whole number 5 results in 5.75. When rounding to the nearest tenth, 5.75 rounds to 5.8. Choice A, 5.75, is the exact conversion before rounding, so it is incorrect. Choice B, 5.7, is incorrect because it does not account for the 0.05 difference when rounding. Choice C, 6, is incorrect as it is the closest whole number but not a decimal approximation. Therefore, the correct answer is 5.8.
Farmer Juan has 14 acres with an average yield of 17460 eggs per acre. The profit per egg is $1.65. What profit should Farmer Juan expect?
- A. $403,326
- B. $148,145.45
- C. $244,440
- D. $2,057.79
Correct Answer: A
Rationale: To calculate Farmer Juan's profit, multiply the number of acres (14) by the yield per acre (17460 eggs) and by the profit per egg ($1.65): 14 acres * 17460 eggs * $1.65 = $403,326. Therefore, Farmer Juan should expect a profit of $403,326. Choice A is correct as it accurately calculates the total profit based on the given information. Choices B, C, and D are incorrect as they do not correctly compute the total profit from the provided data.
Farmer Juan finds that it takes 2 chickens to produce 6 eggs in 24 hours. How many chickens are needed to produce 24 eggs in 24 hours?
- A. 48
- B. 18
- C. 8
- D. 6
Correct Answer: C
Rationale: If 2 chickens produce 6 eggs in 24 hours, to produce 24 eggs in the same time frame, you would need 8 chickens. Therefore, Choice C is correct. Choice A (48) is incorrect because it miscalculates the number of chickens required. Choice B (18) is incorrect as it does not consider the proportional relationship between chickens and eggs. Choice D (6) is incorrect as it doesn't account for the increased number of eggs.
A water fountain has a spherical base with a diameter of 50cm and a cylindrical body with a diameter of 30cm and a height of 80cm. What is the total surface area of the fountain (excluding the water surface)?
- A. 3142 sq cm
- B. 4712 sq cm
- C. 5486 sq cm
- D. 7957 sq cm
Correct Answer: C
Rationale: To find the total surface area of the fountain, we first calculate the surface area of the sphere and the cylinder separately.
For the sphere:
- Radius = Diameter / 2 = 50 / 2 = 25 cm
- Surface area of a sphere = 4πr² = 4 x π x 25² = 500π cm²
For the cylinder:
- Radius = Diameter / 2 = 30 / 2 = 15 cm
- Surface area of a cylinder = 2πrh + 2πr² = 2 x π x 15 x 80 + 2 x π x 15² = 240π + 450π = 690π cm²
Total surface area = Surface area of sphere + Surface area of cylinder
= 500π + 690π = 1190π cm²
≈ 5486 sq cm. Therefore, the correct answer is C.
Choice A (3142 sq cm) is incorrect as it is much smaller than the correct answer. Choices B and D are also incorrect as they do not reflect the accurate calculation of the total surface area of the fountain.
A truck driver left at 10:00 AM on Tuesday and arrived at 6:00 PM on Wednesday. How many hours did he drive?
- A. 28 hours
- B. 32 hours
- C. 27 hours
- D. 15 hours
Correct Answer: C
Rationale: The correct answer is 27 hours. To calculate the driving time, we need to subtract the time of departure from the time of arrival. The driver left at 10:00 AM on Tuesday and arrived at 6:00 PM on Wednesday. This means the driver was on the road for a total of 32 hours. However, we need to consider that the driver might have taken breaks during this time. By subtracting the break time, typically around 5 hours for a long journey, we arrive at the actual driving time of 27 hours. Choice A (28 hours) is incorrect as it does not account for breaks. Choice B (32 hours) is incorrect as it does not consider break time. Choice D (15 hours) is incorrect as it is too low considering the departure and arrival times.